Apparatus for the centrifugal casting of hollow bodies



Nov. 8, 1927.

H. BURCHARTZ APPARATUS FOR THE CENTRIFUGAL CASTING '01- HOLLOW BODIES Filed Jan. 14. 1925' 15 ings which exemplify Patented Nov. 8, 1927.

UNITED STATES PATENT OFFICE.

HEINRICH BUBCHARTZ, OF GELSENIKIRCHEN, GERMANY.

APPARATUS FOR THE CENTRIF UGAL CASTING OF HOLLOW BODIES,

.Applicationfiled January 14 1925, Serial No. 2,393, and in Luxemburg November 11, 1924.

This invention relates to that class of casting machines in which the centrifugal force inherent in rotary. molds is utilized to determine the form and dimensions of hollow bodies.

The primary object of this invention is to provide an improved construction for the apparatus whereby the moltenmetal may be supplied to a machine of this character In suitable quantities and free from impurit es. Other and further objects of invention will appear in the specification and be pointedoutin the appended claims, refer-v ence being had to the accompanymg drawmy invention in a preferred embodiment and in which- Figure 1 is a diagrammatic slde elevatlon partly in section of a centrifugal casting machine embodying the principles of the pres cut invention;

Figure 2 is a side elevation of a su1table ladle whereby a suitable constant head may be sustained a submerged outlet, parts being broken away and parts shown in section;

Figure 3 is a side elevatlon of a modified form of ladle, parts being broken away and parts shown in section, and V Figure 4 is a longitudinal section of a distributing trough employed in carrying out the present invention.

- The. most important considerations met with in molding hollow bodies by centrifugal casting processes, are those connected.

with determining the proper thickness for the walls, the quantity of the metal to be supplied, and the rate at' which such metal,

is to be supplied. While the velocity at which the metal is supplied to a rotary mold, maybe regulated by comparatively simple expedients, it is more diflicult to supply the molten metal in exactly the proper quantlties in any particular case. Thus, according to well known expedients theretofore employed, such, for example, as tilting ladles in connection with supply troughs arranged at more or less of an incline and notwithstanding such well known expedients as varying the tilting speed and regulating the tilting motion by hydraulic pressure, it is diflicult to obtain a uniform discharge of metal. A further drawback in the use of tilting ladles, has resided in the difiiculty met with in preventing impurities such as slag and foam which floats upon the surface of the molten metal, from reaching the mold on the discharge outlet.

in molten metal discharged from and thus impairing the quality of the cast- For the purpose of overcoming the above difliculties, the present invention contemplates suitable and effective means for regulating the discharge ofmolten metal from an opening of exactly predetermined size which may be varied to meet the requirements of each particular case and for maintaining an exactly predetermined pressure For this purpose, the molten metal may be discharged from a submerged outlet under a uniform pressure, which may be maintained, for example, by supplying molten metal to the ladle or other container at the same'rate at which it is being discharged 'from the submerged outlet. Suitable means for varying or regulating the size of the discharge outlet, may consist of a slide provided with apertures of difi'erent sizes, or of interchangeable disks having apertures of diflerent sizes. Said disks may be advantageously employed since they are readily replaceable in the event that hey become clogged or otherwise unfit.

Referring more particularly to the drawings in the embodiment of my invention shown in Figure 1, a rotary mold 1 is suitably mounted within a housing 2 carried by '-Wheels 3 movable upon a track 4 for the purpose of reciprocating said mold with respect to a distributing trough 5 which in the present embodiment of my invention is mounted in a pier 6. A crane ladle 7 pivotally supported at 8 in a hanger 9 is suitably mounted to pour directly into a container or receptacle 10 pivotally mounted upon trunnions 11 to adapt it to be moved into dotted line position for emptying and repairs after a pour. Said container or receptacle 10 is provided with an opening 12 in its forward wall, said opening being partly closed by a removable disk 13 provided with a discharging outlet 14. Said disk 13 may be one of a number of replaceable disks provided with discharge openings of difl'erent sizes to correspond to requirements of particular conditions. Suitable means for regulating the pressure upon the molten metal discharged thru outlet 14 may be provided by a spill-way 15 which determines the upper level of the molten metal with respect to the discharge outlet 14. Suitable means for, varying the upper level of the molten metal as well as the discharge opening 145 with respect to the axis of the rotary mold, may

be provided by raising and lowering a slide upon which the container or receptacle 10 is mounted by trunnions 11. If desired an alternative construction for varying the size of the discharge opening, may be provided in the form of a slide having a series of openings ofdifierent sizes corresponding to those in the several disks 13. If desired, the height ofthe metal in the container or receptacle 10 may be more readily controlled by use of a gauge for determining the upper level of the molten metal. It will be understood from this description that the metal poured from the crane ladle 7 into the receptacle 1 0 in sufiicient quantity to maintain the upper level of the molten metal at a limit determined by the spill-way 15, the molten metal discharges thru the out let 14 under a constantly maintained head into the distributor 5 by which it is delivered to the centrifugal mold 1. During this operation, a suitable velocity is imparted to the molten metal passing thru the distributing trough 5 by raising or lowering the receptacle or-container 10 relatively to the distributing trough 5. This feature of my invention is equally applicable to a machine in which the distributmg trough is arranged on the level or at an inclination to the axis of the centrifugal mold. After the casting operation is completed, the container or receptacle 10 is in the present embodiment moved rearwardly on its trunnion 11 to empty the residual metal therein into a suitable basin 16 disposed for that purpose. In practice it is advisable to have a plurality of such containers 10 so that while one is being cleaned and prepared for further use another can be placed in operation in its stead.

According to the modification shown in Figure 2 of the drawings, a crane ladle 17 mounted on trunnions 18 within a hanger 19 is provided with a discharge outlet 20 submerged below the level 21 of the molten metal contained therein. According to this construction, the ladle is adapted to maintain a uniform pressure upon the molten metal discharged thru outlet 20 either by tilting said ladle to-maintain the upper surface of the metal at a predetermined distance above said opening 20 or by having additional molten metal poured therein to maintain the constant level Without tilting said ladle. A further modification is shown in Figure 3 wherein a substantially cylindrical ladle 22 is provided with a discharge outlet 23 and trunnioned at 24 in a suitable hanger 25. It will be seen thatas the upper level 26 of the molten metal falls, the discharge outlet 23 may be moved downwardly to compensate therefor and thus to maintain .a constant predetermined pressure upon said outlet. Referring now to Figure 4, the distributing trough 27 shown therein is provided with agate or barrier 28 thru I which extends a constricted opening 29 for regulating the flow of metal along'the m clined distributing trough. To the rear of said gate or barrier 28 the distributing trifugal mold as hereinbefore described provides an effective control over the quantity of metal delivered to said mold and at the same time enables a more effective regulation of the frequency to which the wall of the cast body is molded. Furthermore, impurities such as slag, etc., is positively prevented from getting into the mold and the pouring process is thus simplified and improved.

I claim:

1. In a centrifugal casting machine, the combination with a container for molten .metal, said container being provided with a submerged discharge outlet in its side wall and means for maintaining a constant pressure of metal above said discharge outlet, a revolving mold, and means for receiving the molten metal as it is discharged from said outlet, and distributing it longitudinally of said mold.-

2. In a centrifugal casting machine, the combination with a container for molten .me'tal, said container being provided with a submerged discharge outlet in its sidewall and means for maintaining a constant pressure of metal above said discharge outlet, 11

revolving mold, and means for receiving the molten metal as it is discharged from said outlet, and distributing it longitudinally of said mold, said distributing means com prising a trough provided with a barrier aving a submerged opening therethru. 3. In a centrifugal casting machine, the combination with a centrifugal mold, of a distributing trough therefor, a receptacle for molten metal, said receptacle having in its side wall a submerged opening discharging into said distributing trough, and means for raising and lowering said receptacle with respect to said distributing trough.

4:. In a centrifugal casting machine, the combination with a centrifugal mold, of a distributing trough therefor, a receptacle for molten metal, said receptaclehaving in its side wall a submerged opening of vari' able size discharging into said distributing trough, and means for raising and lowering said receptacle with respect to said distributing trough.

5. In a centrifugal casting machine, the combination with a centrifugal mold and a distributing trough leading thereto, of a receptacle for molten metal provided with a submerged discharge outlet in its side Wall and a spill-way to maintain a uniform head of metal above said outlet, said container being movable upwardly and downwardly with respect to said distributing trough to vary the head under which the metal from said container discharges into said trough, said receptacle being provided with means for varying the size of the discharge outlet therein.

combination with a centrifugal mold and a distributing trough leading thereto, of a recetaclc for molten metal provided with a su merged discharge outlet in its side wall, said receptacle being pivotally mounted, and means for tilting sald receptacle to maintain the upper level of the molten metal at a constant height above said outlet.

7. In a centrifugal casting machine, the combination with a centrifugal mold and a distributing trough leading thereto, of a receptacle for molten'metal provided with a submerged discharge outlet in its side wall and a spill-way to maintain a uniform head of metal above said outlet and control means for determining the upper level of the 'molten metal. 6. In a centrifugal casting machine, the

HEINRICH BURGHARTZ. 

